Clothes treatment agent release device, washing machine and control method thereof

A clothes treatment agent release device, comprising:

• a storage cavity in which a clothes treatment agent being stored;
• a release cavity being provided with a liquid outlet and a liquid inlet communicating with the storage cavity, a liquid inlet one-way turn-on part being arranged at the liquid inlet, and a liquid outlet one-way turn-on part being arranged at the liquid outlet;
• a piston mechanism being arranged in the release cavity in a reciprocating motion mode;
• and
• a driving mechanism being connected with the piston mechanism;
• wherein
• the driving mechanism drives the piston mechanism to do reciprocating motion in the release cavity, the liquid inlet one-way turn-on part or the liquid outlet one-way turn-on part respectively and unidirectionally turns on the liquid inlet or the liquid outlet in the reciprocating motion of the piston mechanism, and the clothes treatment agent in the storage cavity is sucked into the release cavity from the liquid inlet, and is discharged and released from the liquid outlet.